In a certain city the temperature (in degrees Fahrenheit) $t$ hours after 9am was approximated by the function $$T(t) = 40 + 14 \sin \left(\frac{\pi t}{12} \right)$$ Determine the temperature at 9 am.
Determine the temperature at 3 pm.

Find the average temperature during the period from 9 am to 9 pm.